Praying Mantises Sport the World's Smallest 3D Glasses

By Richard Adhikari
Apr 29, 2014 7:17 AM PT

What might be the world's smallest 3D glasses have been developed for praying mantises.

People, horses, falcons, cats, monkeys and even toads have 3D vision -- but until 1983, everyone thought that invertebrates didn't, because their brains were so small and simple. That year, Samuel Rossel of the University of Zurich in essence said that
mantises had 3D vision.

The research, publicized by the university last week, aims to establish whether mantis 3D vision is capable of only range-finding or also can break camouflage. During World War 1, 3D photos made it easier to identify camouflaged military structures.

The Newcastle study will explore how mantises, with their tiny brains, can process 3D images. The praying mantis' brain has about one million neurons compared to tens of billions in the human brain.

The research could lead to development of a machine 3D algorithm that would take binocular video streams as input for translating into actions. Such an algorithm might be simpler than existing ones, while outperforming them.

How the Experiment Will Be Performed

The 3D glasses will be attached to a mantis' face with beeswax. The mantis will then be put in front of a 3D computer screen and shown a moving image for it to strike.

Two high-speed cameras, recording at 1,000 frames a second, will record the mantis' position from below and from the side. The cameras interface with a computer, which will download the images and analyze the data. The researchers developed automated 3D display, data collection and analysis technology for the experiment.

Extracellular activity in the mantis' nervous system will be recorded, with the researchers using silver wire electrodes to measure the electrical spikes produced by a subset of neurons. [*Correction - May 1, 2014]

More on the 3D Glasses

The 3D glasses are actually circular polarizing filters, because insect eyes are sensitive to linear polarization but not circular polarization. [*Correction - May 1, 2014]

These filters are the same as those used for 3D TVs and computer monitors.

A spokesperson for the Newcastle University research program was not immediately available to provide further details.

The Things that Mantises Do

Their triangular heads maximize the 3D vision baseline; they have a binocular overlap of more than 70 degrees; and they have forward-facing fovea -- that part of the eye that sees things in great detail -- in their eyes.

Mantises previously have inspired technological developments. They tilt their heads left and right when they look, apparently to obtain depth perception, and this led to the development of a mathematical model for depth estimation, the
mantis head camera.

Implications of Simpler Algorithms

"In computing, the more pixels and attributes you compare, the more accurate and complex the algorithm," Jim McGregor, principal at Tirias Research, told TechNewsWorld.

Generally speaking, a simpler algorithm would lead to faster processing, lower power consumption and longer battery life -- and possibly the ability to process more data with a greater level of accuracy, McGregor said. Processing speed and accuracy could play a critical role in robotics.

It's All in the Eyes

Mantises' eyes are disproportionately large, so it might be that the 3D images are being processed in them rather than in the insects' brains.

"This is very likely, because it would speed processing significantly," Rob Enderle, principal analyst at the Enderle Group, told TechNewsWorld.

If that is the case, it could provide another option for equipping robots to view 3D, and allow them to get their job done sooner, he speculated. It would "allow a more modular approach to a variety of vision problems."

Still, mantis eyes can't match up to those of the
mantis shrimp, which apparently can see ultraviolet and infrared, and view two forms of polarized light. They see in 3D and their visual system has been compared to a satellite.

Richard Adhikari has written about high-tech for leading industry publications since the 1990s and wonders where it's all leading to. Will implanted RFID chips in humans be the Mark of the Beast? Will nanotech solve our coming food crisis? Does Sturgeon's Law still hold true? You can connect with Richard on
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